[mythtv-users] mythburn

[stuart]

On 03/06/2011 12:19 PM, Michael T. Dean wrote:
> On 03/06/2011 11:10 AM, stuart wrote:
>> On 03/06/2011 08:02 AM, Michael T. Dean wrote:
>>> On 03/06/2011 08:10 AM, stuart wrote:
>>>> [Trying with a better subject line.]
>>>>
>>>> On 03/05/2011 09:55 AM, Will Dormann wrote:
>>>>>> On 3/5/11 9:09 AM, stuart wrote:
>>>>>>>> Hi...
>>>>>>>>
>>>>>>>> When making DVDs w/chapters mythburn quits saying it can not find the
>>>>>>>> last chapter.  When making DVDs w/o chapters mythtv burns the DVD, but
>>>>>>>> it is missing the last bit of the recording.
>>>>>> mythburn.log is probably a good place to start.
>>>> Ok, here is a portion of mythburn.log file where I created a DVD from a
>>>> mythtv recording.  Notice how it can be inferred the last bit of the
>>>> transcoded recording is missing (i.e. the missing "chapter 2"):
>>>>
>>>>
>>>>       ERR:  Cannot jump to chapter 2 of title 1, only 1 exist
>>>>       ERR:  in VTSM pgc 0, button 2
>>>>       ************************************************************
>>>>       ERROR: Failed while running dvdauthor. Result: 1
>>>>       ************************************************************
>>>>
>>>> Missing the last 20 minutes of a 90 minute show when I created a DVD
>>>> from another recording with out using chapters starts to make sense.
>>>> It's as if mythburn or a tool that mythburn is using does away with the
>>>> last bit of a recording.  Perhaps the entire last chapter!
>>>>
>>>> Has anyone else see this?  Better yet, has anyone else work out what the
>>>> problem is?
>>> http://code.mythtv.org/trac/ticket/8438
>>>
>>> Read all of the information there, including
>>> http://code.mythtv.org/trac/ticket/8438#comment:8 .
>> Hey, thanks Mike for the links.  However, I'm thinking this is not
>> exactly the problem I am seeing.  I read the thread and downloaded the
>> patch.  It didn't go into my copy of mythburn.py.  Upon inspection I see
>> where about 90% of the patch is already part of my distribution of
>> mythburn.py.
>
> Right, which is exactly what Paul said in comment 8--that he put the
> patch to make the chapter list not end with a comma in, and that he said
> it was unrelated to the bug.
>
> In other words, the description of the bug--by a user who wasn't sure
> what was happening--does not identify the actual cause of the bug.  Paul
> said that he's pretty certain that the actual cause of the problem is a
> failure to process the video file (corrupt video, video encoded with
> options the processing program (mythtranscode or projectx) can't handle,
> ...) and that until someone finds
>
>>     Looking at the code I see where adding the comma to the
>> auto generated XML file had been changed in both the patch and in my
>> copy of mythburn.py. (This extra coma was seen as the root of the
>> problem in myth bug thread 8438.) I then checked the XML file generated
>> (dvdauthor.xml) in one of my failed attempts to create a DVD from a
>> mythtv recording.  Interestingly it appears to be formed correctly.
>> Well, that is to say, there was no "dangling coma" at the end of the vob
>> chapter list.  However, I know the recording is about 90 minutes.  I
>> know the DVD fails (as far as I am concerned) because it cuts off the
>> last bit of the recording.  I see chapter marks set up at roughly 7
>> minute intervals.  I see one at 37 minutes, 44 minutes and 52 minutes.
>> If the recording was 90 minutes long I should see another at about 59 or
>> 60.  And perhaps one more after that.  Now I am thinking there really is
>> a missing chapter.  That is, it was not an extra comma as much as a
>> failure to add the last chapter to the dvdauthor.xml file.
>>
>> Maybe this bit of code starting on line 735 of dvdauthor.xml:
>>
>>>       chapters=[]
>>>
>>>       thumbList=[]
>>>       starttime=0
>>>       count=1
>>>       while count<=numofchapters:
>>>           chapters.append(time.strftime("%H:%M:%S",time.gmtime(starttime)))
>> Should read:
>>
>>>       chapters=[]
>>>
>>>       thumbList=[]
>>>       starttime=0
>>>       count=0
>>>       while count<=numofchapters:
>>>           chapters.append(time.strftime("%H:%M:%S",time.gmtime(starttime)))
>> Note where "count" has been changed to start at zero instead of one. As
>> it is not being used to index anything in the code, I'm thinking this
>> might safely pick up the last missing chapter.
>
> That's possible.  Worth your testing, and if it (reliably) fixes the
> issue, please let us know.  (I don't know that particular code, though,
> so I can't say from a design standpoint which should be right.)
>
> But it's also quite possible that the processing program just fails.
> I've noticed that due to changes in the encoding options used by my
> local broadcasters, mythtranscode tends to fail on>50% of new
> recordings, whether I'm doing lossless transcoding or lossy.  So, the
> idea that it may be the processing program failing makes sense to me
> (and would explain why the reporter saw his fix "work"--because on a
> different run, the program didn't crash while processing the video).
>
> Mike


Sorry Mike I've been slow to replay.  I lost my mythburn logs and have 
not had time to repeat the test to create new logs to post.  Regardless 
I did try the code/script modification I talked about above and it did 
not help.  It still bombed out with errors.  So much for us simple 
thinkers.  It is probably as you pointed out.  That is the media is 
giving the tools a hard time resulting in files that are not possible to 
work with.

Have you heard anything more about this problem?

Is there a better place (reads: more specific list somewhere) to talk 
about it?

-thanks